Load-carrying structures that are open at the top are primarily used for bulk goods, as well as other goods that can be loaded from above. However, these goods are often sensitive to moisture, or can easily be blown away by the airflow generated during travel. For this reason, cover systems are often used, usually taking the form of sliding or roll-over tarpaulins. However, pulling such tarpaulins over the load opening can be difficult as the mechanism often jams and/or is restricted by the load itself. This means that valuable time may be lost in the case of unexpected downpours or hailstorms.
U.S. Pat. No. 6,402,233 B2 first describes a cover system made of two roof segments as the state of the art; this system can be swivelled between closed position and open position, with each roof segment being rigidly attached to a drive shaft positioned in the region of the upper longitudinal edges of the side walls. The drive shafts are driven by a hand-operated chain drive. However, U.S. Pat. No. 6,402,223 B2 regards this swivel mechanism as relatively cumbersome and disadvantageous. The suggested alternative is a system where both roof segments are operated by means of four link rods, with two link rods being rigidly attached to each drive shaft.
A vehicle with a powered swivel mechanism is also familiar from DE 10 2007 043 818 B4.